The present invention relates to a switching power supply device and a semiconductor integrated circuit, more particularly to, for instance, a technique that can be effectively applied to a switching power supply device for converting a high voltage into a low voltage.
Examples of transformer type synchronous rectifying converter include what are disclosed in the Japanese Unexamined Patent Publications Nos. 2001-346380 and 2001-008444.
[Patent Reference 1] Japanese Unexamined Patent Publication No. 2001-346380
[Patent Reference 2] Japanese Unexamined Patent Publication No. 2001-008444